Those look like the large connectors I use on the solar power cables for the house.

Mine are 2 gauge and even much larger. I have a hydraulic crimper for them Those I trust. The ones everyone uses in cars normally I don't trust.

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Just BMW's - All cars and trucks was two pages long
1994 318is
1997 528i
2000 323i
2001 X5 3.0 auto
2005 X5 3.0 auto
2011 535xi auto
2013 X5 xdrive35 Turbo
More are at my website

Aftermarket E53 Radio Install